The present invention relates to a cartridge having sheets and provided with a visually readable, electrically updateable display having a measurable parameter.
Current home printers consume blank sheets either by being hand fed one sheet at a time, from a cartridge, or from media tray. In each scenario, the user can determine the number of sheets remaining by visual inspection. Since these sheets are not light sensitive, the media is often visible from outside the printer housing. Typically, printers will also have a xe2x80x9cload mediaxe2x80x9d indicator that informs the user that the cartridge or media tray is empty. The user will then add fresh blank sheets to the existing cartridge or media tray. The media is often purchased in bulk, and only a portion of the bulk media is loaded into the cartridge or media tray at one time. The unused sheets are usually left in the cartridge or media tray for future use.
Today""s home printers have become more sophisticated, even to the extent of using photosensitive and/or environmentally sensitive sheets for printing high quality images and photographs. By nature, these photosensitive sheets must be kept in the dark prior to use, meaning printer cartridges containing photosensitive sheets are light tight. Photosensitive sheets usually have special storage requirements as well, meaning that when not in use it should be kept in a special container and not subjected to extremes in temperature and/or humidity. The result is that a cartridge containing photosensitive sheets can be partially used in a printer, then removed and stored for later use. The cartridge typically comes with a designated number of sheets, and once fully consumed, the cartridge is discarded. If the sheets in the cartridge are not fully consumed, the user is left with a partially consumed cartridge. Unless the user makes a manual notation regarding the number of sheets previously consumed, the user has no way of determining the number of sheets remaining in the cartridge, or if there isn""t any sheet at all.
Accordingly, it is an object of the present invention to provide an electrically actuated display on a cartridge for indicating the number of sheets in the cartridge.
It is another object of the present invention to provide a display on a cartridge that presents an image to a viewer even when the voltage to the display is removed.
It is another object of the present invention to provide a display on a cartridge that presents an image to a viewer even when the voltage to the display is removed, and is electrically readable by an apparatus.
It is yet another object of the present invention to provide a display on a cartridge that presents an image to a viewer even when the voltage to the display is removed, is electrically readable by an apparatus, and can be updated by the apparatus.
It is still yet another object of the present invention to provide an apparatus that can electrically read and write to a display on a cartridge that presents an image to a viewer.
These objects are achieved in a removable cartridge with sheets that are to be removed from the cartridge and used by an apparatus comprising:
a) a housing for containing the sheets which are to be sequentially used by the apparatus when the cartridge is inserted into the apparatus;
b) means provided in the housing for permitting sheets to be fed by the apparatus from the cartridge; and
c) a display provided on the housing which is viewable by a user when the cartridge is removed from the apparatus to indicate the number of sheets remaining in the cartridge, including:
i) the display having a plurality of selectable digit elements each of which corresponds to a particular number, each selectable digit element containing cholesteric liquid crystals when selectively activated indicate a number that corresponds to the number of sheets remaining in the cartridge, and provide a measurable parameter;
ii) the apparatus including circuitry being responsive to the measurable parameter to determine the number provided on the display and to change the selectable digit elements to indicate a new number in response electrical signals provided by the apparatus indicating that a sheet has been removed from the cartridge and inserted into the apparatus and which continues to indicate the present number of sheets remaining in the cartridge after such cartridge has been removed from the apparatus.
It is a feature of the present invention that the display on the cartridge presents an image when high voltage to the display is turned off.
It is a further feature of the present invention to provide a display on a cartridge that has a measurable parameter.
It is a further feature of the present invention to provide an apparatus having means to measure said measurable parameter on a cartridge.
It is a further feature of the present invention to provide an indication on the cartridge of the number of sheets remaining in the cartridge.